Lancing device and lancet

ABSTRACT

A lancing device and lancet are provided with depth-control, lancet ejection, and/or guidance mechanisms. The depth-control mechanism includes a dial rotationally mounted at a distal end of the housing of the lancing device, the dial being coupled to a linkage whereby rotation of the dial imparts translational movement to a stop surface of the linkage to limit the stroke of the lancet and thereby control lancing penetration depth. The ejection mechanism includes an ejector that is advanced into contact with a transversely flared flange of the lancet to discharge the lancet from the lancing device. The guidance mechanism includes an inner guidance housing for restricting out-of-axis movement of a lancet carrier.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/138,768, filed Dec. 18, 2008, the entirety ofwhich is hereby incorporated herein by reference for all purposes.

TECHNICAL FIELD

The present invention relates generally to the field of medical devices,and more particularly to lancets and lancing devices for blood samplingand testing.

BACKGROUND OF THE INVENTION

Lancets and lancing devices are utilized for penetrating the skin of ahuman or animal subject at a lancing site to obtain a sample of blood orother body fluid for medical testing, as in blood-typing orblood-glucose testing. Known lancing devices commonly include a housingcontaining a drive mechanism, a charging mechanism for energizing thespring or other drive means of the drive mechanism, and a releasemechanism for releasing the drive mechanism upon actuation. A lancet istypically propelled by the drive mechanism from a retracted positionwithin the housing to an extended position wherein a sharp tip portionof the lancet projects from the housing to prick the subject's skin at adesired lancing site. A depth-control mechanism can optionally beprovided to adjust the penetration depth of the lancet.

The lancet is typically a disposable component that is removably mountedinto a receiver or lancet carrier portion of the drive mechanism of alancing device. A used lancet typically is removed from the lancetcarrier after sampling for disposal. An ejection mechanism canoptionally be included for discharge of the used lancet from the lancingdevice. A new, sterile lancet is then replaced into the lancet carrierfor further sampling. Lancets typically comprise a sharp metal tip inthe form of a needle or blade. The needle or blade is typically embeddedin a plastic body that has a size and shape configured for releasableengagement with the receiver or lancet carrier of a lancing device. Thesharp tip of the lancet is commonly embedded in a removable plastic capto maintain sterility and prevent inadvertent sticks prior to use. Theendcap may be replaceable onto the lancet after use to re-cover thesharp lancet tip for safety and hygienic purposes.

It is to the provision of improved lancing devices and lancets that thepresent invention is primarily directed.

SUMMARY OF THE INVENTION

In example embodiments, the present invention provides an improvedlancing device, an improved lancet, and a system including a lancingdevice with a proprietary or device-specific lancet. Example embodimentsinclude an improved depth-adjust mechanism for selectively varying thepenetration depth of the lancet, an improved lancet ejector system usinga protrusion or surface of the lancet to eject a used lancet from thelancing device, and/or an improved guidance system for guiding the pathof travel of the lancet along its lancing stroke.

In one aspect, the invention relates to a lancing device including ahousing, a lancet carrier mounted within the housing for movementbetween a retracted position and a lancing position, and a depth-controlmechanism. The depth-control mechanism includes a dial rotationallymounted relative to the housing, and a linkage mechanism coupled to thedial and having a stop member for limiting travel of the lancet carrierat the lancing position.

In another aspect, the invention relates to a lancing system including alancet and a lancing device for receiving and discharging said lancet.The lancet includes a lancet body, a sharp lancing tip projectingaxially from a proximal end of the lancet body, and a flared flangeprojecting transversely from the lancet body. The lancing deviceincludes an ejection mechanism having an abutment member for contactingthe flared flange of the lancet and ejecting the lancet from the lancingdevice.

In another aspect, the invention relates to a lancet including a lancetbody, a sharp lancing tip projecting axially from a proximal end of thelancet body, and a flared flange projecting transversely from the lancetbody.

In still another aspect, the invention relates to a lancing systemincluding a lancet and a lancing device for receiving and dischargingsaid lancet. The lancet includes a lancet body, a sharp lancing tipprojecting axially from a proximal end of the lancet body, and a recessin the lancet body. The lancing device includes an ejection mechanismhaving a protrusion for engaging the recess in the lancet body andpushing on the lancet body to eject the lancet from the lancing device.

In another aspect, the invention relates to a lancet including a lancetbody, a sharp lancing tip projecting axially from a proximal end of thelancet body, and a recess in a side of the lancet body for engagementwith an ejector of a lancing device

In another aspect, the invention relates to a lancing device including ahousing, a lancet carrier mounted within the housing for movementbetween a retracted position and a lancing position, and a depth-controlmechanism. The depth-control mechanism includes a dial rotationallymounted relative to the housing, and a linkage coupled to the dial andhaving a contact face for limiting travel of the lancet carrier at thelancing position.

In another aspect, the invention relates to a lancing system including alancet and a lancing device for receiving and discharging the lancet.The lancet includes a lancet body, a sharp lancing tip projectingaxially from a proximal end of the lancet body, and a flared flangeprojecting transversely from the lancet body. The lancing deviceincludes an ejection mechanism comprising an abutment face or protrusionfor contacting the flared flange of the lancet and ejecting the lancetfrom the lancing device.

In still another aspect, the invention relates to a lancing systemincluding a lancet and a lancing device for receiving and dischargingthe lancet. The lancet includes a lancet body, a sharp lancing tipprojecting axially from a proximal end of the lancet body, and a slot,pocket, or similar cavity in the side of the lancet body. The lancingdevice includes an ejection mechanism comprising an abutment face(protrusion) for contacting the slot, pocket, or similar cavity in theside of the lancet body and ejecting the lancet from the lancing device.

In another aspect, the invention relates to a lancing device includingan outer housing, a lancet carrier translationally movable within thehousing, and an inner guidance housing mounted within the outer housingfor constraining the lancet carrier to axial movement along a linearlancing stroke.

In another aspect, the invention relates to a lancet including a lancetbody, a sharp lancing tip projecting axially from a proximal end of thelancet body, and a flared flange projecting transversely from the lancetbody.

In still another aspect, the invention relates to a lancet includes alancet body, a sharp lancing tip projecting axially from a proximal endof the lancet body, and a slot, pocket, or similar cavity in the side ofthe lancet body for interaction with an ejector.

These and other aspects, features and advantages of the invention willbe understood with reference to the drawing figures and detaileddescription herein, and will be realized by means of the variouselements and combinations particularly pointed out in the appendedclaims. It is to be understood that both the foregoing generaldescription and the following brief description of the drawings anddetailed description of the invention are exemplary and explanatory ofpreferred embodiments of the invention, and are not restrictive of theinvention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a lancing system including a lancingdevice and a lancet according to an example embodiment of the presentinvention.

FIG. 2 is another perspective view of the lancing device of FIG. 1, withits outer housing removed to show internal components.

FIG. 3 is a bottom view of the internal mechanism of the lancing deviceof FIG. 1.

FIGS. 4A, 4B and 4C show a sequence of adjustment of a depth-controlmechanism subsystem of the lancing device of FIG. 1.

FIGS. 5A and 5B show a sequence of operation of a lancet-ejectionsubsystem of the lancing device of FIG. 1.

FIGS. 6A, 6B and 6C show a sequence of operation of the lancing deviceof FIG. 1, in its rest, charging and firing positions, respectively.

FIG. 7 shows a lancet guidance system of the lancing device of FIG. 1.

FIGS. 8A, 8B and 8C show a sequence of adjustment of a depth-controlmechanism subsystem of a lancing device according to another exampleembodiment of the invention.

FIG. 9 is a perspective view of a lancet according to an exampleembodiment of the invention.

FIGS. 10A, 10B and 10C show a lancet and lancet ejection mechanismaccording to another embodiment of the invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

The present invention may be understood more readily by reference to thefollowing detailed description of the invention taken in connection withthe accompanying drawing figures, which form a part of this disclosure.It is to be understood that this invention is not limited to thespecific devices, methods, conditions or parameters described and/orshown herein, and that the terminology used herein is for the purpose ofdescribing particular embodiments by way of example only and is notintended to be limiting of the claimed invention. Any and all patentsand other publications identified in this specification are incorporatedby reference as though fully set forth herein.

Also, as used in the specification including the appended claims, thesingular forms “a,” “an,” and “the” include the plural, and reference toa particular numerical value includes at least that particular value,unless the context clearly dictates otherwise. Ranges may be expressedherein as from “about” or “approximately” one particular value and/or to“about” or “approximately” another particular value. When such a rangeis expressed, another embodiment includes from the one particular valueand/or to the other particular value. Similarly, when values areexpressed as approximations, by use of the antecedent “about,” it willbe understood that the particular value forms another embodiment.

With reference now to the drawing figures, wherein like referencenumbers represent corresponding parts throughout the several views,FIGS. 1-6 show a lancing system comprising a lancing device 10 andlancet 12 according to example forms of the invention. The lancet 12 isoptionally configured in size and shape to be specific or proprietary tothe lancing device of the invention, whereby the lancing device andlancet comprise a complementary system. While the lancing device andlancet can take a variety of forms, in the embodiment of FIG. 1 thelancing device comprises a housing 20 formed of upper and lowerhalf-shells 22 a, 22 b, and optionally a removable proximal endcap 24with a contact face having a lancet opening 26 therein for allowingpassage of the sharp lancet tip during lancing.

FIGS. 2-6 show internal components of a lancing device 10 according to afirst example embodiment of the invention with the outer housingremoved. The lancing device 10 comprises a drive mechanism comprising alancet carrier 30, a drive spring 40 for propelling the lancet carrierfrom a retracted position within the housing to an extended or lancingposition with the sharp lancet tip projecting out of the housing, and areturn spring 42 for returning the lancet carrier to a neutral positionwithin the housing after use. The lancing device further comprises acharging mechanism for retracting the lancet carrier from the neutralposition to the retracted position and compressing the drive spring; andan activation mechanism for releasing the lancet carrier from theretracted position to traverse the lancing stroke from the retractedposition, through the lancing position, and back to the neutralposition. The lancing device optionally further comprises one or more ofa depth-control mechanism, an ejector mechanism, and/or a guidancemechanism, and/or any combination thereof. These mechanisms orsubsystems will be described in greater detail below.

Depth-Control Mechanism

The depth of puncture provided by the lancing device may be adjusted sothat the lancing process generates a sample of the necessary amount ofblood for a successful blood glucose reading or other procedure whilereducing, minimizing or eliminating undue pain to the subject. FIGS. 2-6show a first example embodiment of a depth-control mechanism accordingto the present invention. The depth-control mechanism comprises adepth-adjust dial 60 having a manipulation surface that the patientrotates to easily change the depth of puncture. In example forms, thedial rotates in a horizontal plane along the medial axis of the devicehousing, mounted between the upper and lower half-shells 22 a, 22 b. Inalternate embodiments, the orientation and location of the depth-adjustdial can vary. The depth-control mechanism further comprises a stopmember which acts as a limit of travel for the drive mechanism of thelancing device. In the depicted embodiment, the dial is mounted at thedistal or rearward end of the housing and rotates about an axis ofrotation that is generally perpendicular to the path of travel of thelancet along its lancing stroke. The stop member acts on a transverseprotrusion or other surface of the lancet holder or on a protrusionattached to the lancet holder as the lancet holder moves through itslancing stroke, to arrest the forward motion of the lancet holder andlimit the travel of the lancet thereby defining the proximal or forwardextent of travel of the lancet tip in its fully extended position. Byturning the dial 60, the axial position of the stop member is changedthereby adjusting the point of contact of the lancet holder with thestop member relative to the outer housing, and in this manner the depthof penetration of the lancet is adjusted.

In example embodiments, the depth dial 60 is partially shielded withinthe device housing to improve the safety and user comfort delivered bythe device by avoiding or reducing the incidence of unintentional depthadjustment that could cause unnecessary penetration depth. The rear endof the housing optionally is radiused to generally match the profile ofthe dial 60 with only the outer periphery of the dial projecting beyondthe rearward end of the housing. The dial 60 preferably comprisesnumerical or other indicia visible on a portion of the dial fromexternal of the rear end of the housing or through an opening or cutoutportion of the housing 20 proximal its rear end, indicating the depthsetting to the user. The mechanism of the depth dial preferably providesa smooth transition between depth settings and a clear indication of thedepth setting, for example through a cutout on the housing 20. Aresilient finger or segment of the dial 60 interacts with detents orother indexing features of the housing to provide tactile feedback tothe user of the depth settings, and to retain the depth-adjust mechanismin a set position. The dial 60 optionally has a scalloped, stepped,ridged or knurled edge for ease of adjustment.

The depth-control mechanism comprises a first link 70 and a second link72. The first link 70 has a distal end pivotally coupled to an eccentricpin 62 projecting from the depth-adjust dial 60, and a proximal endpivotally connected by a hinge pin coupling to the distal end of thesecond link 72. The proximal end of the second link 72 comprises acontact face or stop 74 for limiting the stroke of travel of the lancetcarrier 30. Rotation of the dial 60 causes translation of the two-partlinkage 70, 72 in the axial direction, and thereby adjusts the linearpositioning of the stop 74. A larger diameter dial 60 with a smallereccentric offset of the pin 62 from the center or axis of rotation ofthe dial can be used to adjust the depth in small increments with largerrotational increments of the dial for ease of use by users with reducedmanual dexterity. Optionally, the dial 60 moves through one or moreindexed positional settings or through a continuous adjustment range,allowing the user to have an improved tactile feel between depthsettings. Provision of one or both links 70, 72 and/or stop surface 74formed for example of a substantially rigid but resilient materialoptionally acts as a vibration reducer, decreasing the transfer ofenergy or impact sensed by the user upon contact of the lancet carrierwith the stop.

In example embodiments, the depth dial 60 rotates through a range ofmotion of at least about 45-90 degrees to about 270 degrees, for exampleabout 180 degrees. An arcuate flange on the lower face of the dial 60optionally rotates within a corresponding arcuate track or channel inthe lower housing half shell 22 b, or an axle extending from the dialrotates within a corresponding sleeve, bushing or bearing of thehousing. The second link 72 is optionally generally T-shaped in profile,having a transversely extending rib forming the contact face 74 at itsproximal end for limiting the stroke of the lancet carrier. One or bothof the links 70, 72 optionally include guidance features which engagethe lancing device housing or other fixed part of the lancing device andcontrol the motion of the two-part linkage in response to rotation ofthe depth dial. For example, the hinge pin connecting the links 70, 72and/or a finger or fin projecting from the second link 72 optionallyrides in a track in the lower housing shell to maintain axial alignmentof the second link, preventing pivotal movement and constraining thesecond link to axial translation in response to rotation of the dial.Rotation of the dial selectively varies the position of the contact face74, which defines the limit of motion of the lancet carrier 30, therebyadjusting the depth of penetration of the lancet at the lancing site.

The lancet carrier 30 or other portion of the drive mechanism includes acontact element for abutment with the contact face 74 of the stop bar tolimit the travel of the lancet carrier and thereby control thepenetration depth. In the depicted embodiment, the lancet carrier 30comprises a distal extension arm with an end having a contact elementwith a projection or finger 32 mounted thereon. The projection or finger32 extends downwardly to contact the upwardly directed contact face 74of the stop bar as the lancet carrier 30 traverses the forward portionof its lancing stroke. The contact element optionally takes the form ofa sleeve held on the split distal end of the lancet carrier by one ormore resilient barbs to retain the return spring 42 in place on thedistal extension arm of the lancet carrier.

As the dial 60 is rotated, the axial distance that the linkage 70, 72moves is determined by how far the eccentric pin 62 is offset from thecenter of rotation of the dial 60 and the angle through which the dialis moved. Additionally, the distal end of the first link 70 movestransversely due to rotation of the dial to which it is coupled causingpivotal movement of the stop bar. Thus, there are two components of themovement of the first link 70: an axial translational component alongthe long axis of the link 70, and a transverse component perpendicularto the long axis of the link 70. In the depicted embodiment, movementalong the long axis of the stop bar 70 provides the majority of thedepth adjustment. Specifically, for a dial rotation of 180 degrees, thebar 70 moves an axial distance about equal to twice the radialdisplacement or offset of the eccentric pin 62 from the center ofrotation of the dial. For 90 degree rotation of the dial, the stop bar70 moves (along the axis of interest) a distance about equal to theradial displacement or offset of the eccentric pin 62 from the center ofrotation of the dial. The movement in the direction perpendicular to thelong axis of the stop bar is converted to a pivotal toggling movement ofthe link 70.

FIGS. 8A, 8B and 8C show a lancing device 10′, generally as describedabove, and having another embodiment of a depth control mechanismcomprising a “rack and pinion” type gear mechanism to vary the positionof the contact face 74′ of a connector link 70′. The dial 60′ includes atoothed spur gear or pinion 62′ projecting from its center, inengagement with a rack 76 of like gear pitch. The link 70′ isconstrained to translate in only the direction along its long axis,eliminating its ability to rotate. An additional embodiment notillustrated in the figures replaces the rack and pinion gear with a takeup reel on the dial and a push/pull cable connected to the depth stop.

Any number of angular positions of the dial can be converted intodiscrete movements of the depth stop 74, 74′ through the addition ofindexing detents acting on either the dial or the linkage connecting thedial to the stop. Also, while the depicted embodiments show the depthstop acting on only one side of the lancet carrier or firing mechanism,the provision of a linkage which can act on two or more sides of thelancet carrier or firing mechanism is within the scope of the invention.And while the depicted embodiments show a configuration for controllingdepth by limiting the lancing stroke by contact with the back end of thelancet carrier or firing mechanism, the depth control mechanism of thepresent invention also includes embodiments that limit the lancingstroke by contact with any point of the lancet carrier or firingmechanism from the rear up to and including the front where the lancetis engaged.

Ejector Mechanism

FIGS. 2, 3, 5A and 5B show an example embodiment of a lancet ejectionmechanism 100 for removal of a lancet 12 from the lancet carrier 30. Thelancet 12 of the lancing system of the present invention is optionally alow-mass proprietary lancet. Because there is less mass being drivenduring the activation of the device, the lancet may be propelled in andout of the subject's skin faster and with less vibration. Although thepresent invention is not bound to or limited by theory, faster puncturewith a lower mass lancet is believed to reduce pain levels experiencedby the subject. But the low-mass lancet generally has a smaller surfacearea and therefore may be more difficult to handle. Because of the verysmall size of the lancet 12, a large endcap, and/or a collar or flange14 having an expanded or flared transverse dimension is provided at theproximal end of the lancet body for easier manipulation and improvedhandling.

The limited surface area of the lancet's rear face also may not providea sufficient contact surface for use with a rear ejection mechanism.Accordingly, the ejection mechanism of the present invention ejects alancet by pushing on the lancet's flared collar 14 to force it out ofthe lancet carrier. In alternate forms, the system of the presentinvention comprises a lancet with a flange or other protrusionprojecting outwardly from a location other than at the rear of thelancet and an ejector on the lancing device which pushes on thisprotrusion. Alternately, the lancet has a slot, pocket, or hole in thebody and the ejector has a protrusion or other surface which engagesthis hole and pushes on the lancet to eject the lancet from the lancingdevice.

The ejection mechanism 100 comprises an ejector arm 110 slidably mountedbetween the lancet carrier 30 and a release button sleeve 120. Theejector arm 110 includes an ejection actuator 112 providing a userinterface for the user to manually operate the mechanism, and anabutment flange 114 for contacting the flared collar 14 or other contactsurface of the lancet 12 to push the lancet out of engagement with thelancet carrier 30. A notch or opening 122 in the lower face of therelease button sleeve 120 engages a cooperating catch or projection 33of the lancet carrier 30 to limit the forward movement of the lancetcarrier as the lancet is ejected, and leaf springs 124 or other biasingmeans bias the sleeve 120 upward and into engagement with the lancetcarrier unless the release button is pressed downwardly to activate thelancing device. A protrusion 116 on the ejector arm interferes with acooperating protrusion on the housing endcap to prevent operation of theejection mechanism unless the endcap is removed.

FIGS. 10A, 10B and 10C show an alternate ejection mechanism embodiment200 comprising a lancet 212 having a recess 214 such as a slot, pocket,or hole in the lancet body, for example extending along a portion of theside of the lancet body. The ejector 220 has a protrusion 222 or othersurface which extends through a corresponding slot 232 in the lancetcarrier 230 and engages the recess 214 of the lancet 212 and pushes onthe lancet to eject the lancet from the lancing device.

Guidance Mechanism

The guidance mechanism 150 of the present invention is shown in exampleform in FIGS. 2 and 7. While the present invention is not bound to orlimited by theory, it is believed that in general, all else being equal,the smaller the side-to-side movement of the lancet needle (movement ofthe lancet tip transverse to the lengthwise axis of the lancet needle asit moves along the lancing stroke) during the lancing stroke and inparticular as the lancet tip is penetrating the subject's skin at thelancing site, the lower the pain level experienced by the subject. Thus,the guidance mechanism of the present invention is configured toconstrain the lancet to a relatively straight linear stroke or path oftravel.

Minimizing the number of parts involved in the guidance mechanismadvantageously reduces tolerance stacking and play between parts, makingit easier to tightly control/limit the side-to-side movement of thelancet holder as it travels forward. Accordingly, the guidance mechanism150 of the present invention consists of only a single fixed innerguidance housing 160 and a single moving member, namely the lancetcarrier 30. The inner guidance member 160 generally comprises a hollowsleeve having an internal channel with a shape and dimensions configuredto generally match one or more outer surfaces or profile elements of thelancet carrier 30, and thereby allow freely sliding movement of thelancet carrier along the lancing axis A, but minimize out-of-axismovement in any direction.

In example forms, the inner guidance housing 160 comprises a slotdefined between a pair of spaced vertical struts 162, and the lancetcarrier 30 comprises an elongate rib 35 having a profile matching theslot with a close running fit. Additionally or alternatively, the lancetcarrier 30 comprises a flange having an outer profile generally matchingthe inner profile of the channel of the inner guidance housing 160 witha close running fit. The inner guidance housing 160 and/or one or morecomponents affixed thereto is/are engaged within the outer housing 20 atone or more points of contact to prevent relative play therebetween. Inthis manner, the inner guidance housing 160 and the drive mechanismconstitute a drive chassis that can be mated to different outer housingconfigurations.

Charging and Activation

FIGS. 6A, 6B and 6C show a sequence of operation and method of use ofthe lancing system according to an example form of the invention. FIG.6A shows the inner mechanism of the lancing device 10 in a rest orneutral position. The drive spring 40 and return spring 60 areuncompressed (or relatively uncompressed) and in equilibrium. The catch33 of the lancet carrier is engaged in the opening 122 in the lower faceof the release button sleeve 120 to prevent the lancet carrier frommoving substantially forward when a lancet is ejected or installed intothe receiver of the lancet carrier.

FIG. 6B shows the lancing device in a charging position. The user slidesthe charging actuator 180 rearward, compressing the drive spring 40between a retention flange on the lancet carrier and the guidancehousing. The inclined rear face of the catch 33 of the lancet carrier 30presses the release button 121 and release button sleeve 120 downwardagainst the bias of leaf springs 124. As the forward catch surface ofthe catch 33 clears the rear edge of the release button sleeve 120, theleaf springs pop the sleeve and release button back up to retain thelancet carrier 30 in the charged or cocked position.

FIG. 6C shows the lancing device in a firing or activated position. Theuser places the lancet opening 26 of the endcap against the skin at theintended lancing site and presses the release button 121, which movesthe release button sleeve 120 downward against the bias of the leafsprings 124, releasing the catch 33 of the lancet carrier from therelease button sleeve and allows the drive spring to extend and propelthe lancet carrier and lancet forward through the lancing stroke topenetrate the subject's skin at the lancing site. The return spring 42then retracts the lancet tip to a shielded position back within thehousing, returning to the rest or neutral state.

Lancet

FIG. 9 shows a lancet 12 according to an example form of the invention.The lancet includes a lancet body 202, a sharp lancet needle or blade204 having a tip projecting from a proximal end of the lancet body, anda detachable endcap (unshown) having a distal end initially attached tothe proximal end of the lancet body and having the tip of the lancetembedded therein Optionally, the lancet body 202 is configured to beproprietary or device-specific, wherein only a specified lancet designwill engage within a particular lancing device type. For example, thelancet and the receiver of the lancet device can comprisecorrespondingly shaped cross-sectional profiles configured to provide africtional engagement therebetween. In the depicted embodiment, thecross-sectional profiles are generally elliptical as seen best in FIGS.7 and 9, but in alternate embodiments can comprise triangular,polygonal, or other regular or irregular profiles. Alternatively thelancet body may be of standard or universal format.

While the invention has been described with reference to preferred andexample embodiments, it will be understood by those skilled in the artthat a variety of modifications, additions and deletions are within thescope of the invention, as defined by the following claims.

1. A lancing device comprising a housing, a lancet carrier mountedwithin said housing for movement between a retracted position and alancing position, and a depth-control mechanism, said depth-controlmechanism comprising a dial rotationally mounted relative to saidhousing, and a linkage mechanism coupled to said dial and having a stopmember for limiting travel of the lancet carrier at the lancingposition.
 2. The lancing device of claim 1, wherein the linkagemechanism is a two-link mechanism comprising a first link and a secondlink, the first link having a first end coupled to an eccentric pin ofthe dial and a second end connected to the second link, and wherein thesecond link comprises the stop member.
 3. The lancing device of claim 1,wherein the linkage mechanism comprises a pinion mounted to the dial anda stop bar having a first end comprising a rack for cooperativeengagement with the pinion and a second end comprising the stop member.4. The lancing device of claim 1, wherein rotation of the dial drivestranslational movement of the stop member to vary a penetration depth ofthe lancing device.
 5. The lancing device of claim 1, wherein the dialis mounted at a distal end of the housing opposite a lancet opening. 6.The lancing device of claim 5, wherein the distal end of said housingcomprises a cutout portion, and wherein the dial comprises indiciaviewable in the cutout portion and indicating a lancing depth settingcorresponding to the rotational position of the dial.
 7. The lancingdevice of claim 1, wherein the stop member limits travel of the lancetcarrier at the lancing position by direct contact between the stopmember and the lancet carrier.
 8. The lancing device of claim 1, whereinthe stop member limits travel of the lancet carrier at the lancingposition by indirect contact between the stop member a component mountedto the lancet carrier.
 9. A lancing system comprising a lancet and alancing device for receiving and discharging said lancet; said lancetcomprising a lancet body, a sharp lancing tip projecting axially from aproximal end of the lancet body, and a flared flange projectingtransversely from the lancet body; and said lancing device comprising anejection mechanism comprising an abutment member for contacting theflared flange of said lancet and ejecting the lancet from the lancingdevice.
 10. The lancing device of claim 9, wherein the flared flange ofthe lancet projects transversely from the proximal end of the lancetbody.
 11. The lancing device of claim 9, wherein the lancing devicecomprises a housing and an endcap, and wherein the ejection mechanismcomprises means for preventing actuation unless the endcap is removedfrom the housing.
 12. The lancing device of claim 9, wherein the lancingdevice comprises a lancet carrier for releasably engaging the lancet.13. The lancing device of claim 12, wherein the ejection mechanismcomprises means for limiting movement of the lancet carrier as thelancet is ejected.
 14. The lancing device of claim 12, wherein thelancet carrier comprises a receiver for releasably engaging the lancetbody, the receiver having a size and shape configured to frictionallyengage the lancet body.
 15. The lancing device of claim 14, wherein thereceiver and the lancet body have a generally elliptical cross-sectionalprofile.
 16. A lancet comprising a lancet body, a sharp lancing tipprojecting axially from a proximal end of the lancet body, and a flaredflange projecting transversely from the lancet body.
 17. The lancet ofclaim 16, wherein the flared flange projects transversely from thelancet body about substantially the entire periphery of the lancet body.18. The lancet of claim 16, wherein the flared flange projectstransversely from the lancet body at the proximal end of the lancetbody.
 19. The lancet of claim 16, wherein the flared flange projectstransversely from the lancet body between the proximal end of the lancetbody and a distal end of the lancet body.
 20. The lancet of claim 16,wherein the lancet body has a generally elliptical cross-sectionalprofile.
 21. A lancing system comprising a lancet and a lancing devicefor receiving and discharging said lancet; said lancet comprising alancet body, a sharp lancing tip projecting axially from a proximal endof the lancet body, and a recess in the lancet body; and said lancingdevice comprising an ejection mechanism having a protrusion for engagingthe recess in the lancet body and pushing on the lancet body to ejectthe lancet from the lancing device.
 22. A lancet comprising a lancetbody, a sharp lancing tip projecting axially from a proximal end of thelancet body, and a recess in a side of the lancet body for engagementwith an ejector of a lancing device.